With few regulations on air quality and people packing into cities at a staggering rate, urban air quality in developing countries is exceedingly poor. And it's having a huge impact on global health.
Tiny air particles, from cars and dirty power plants, that can penetrate the lungs and enter the bloodstream contribute to heart disease, lung cancer, asthma, and acute lower respiratory infections. At high levels these tiny particles exacerbate the health problems. According to a new study from the World Health Organization, the world's cities are, on average, exceeding WHO's recommended air quality guidelines by three times. WHO measures particles under 10 micrometers or less and the amount recommended amount is 20 micrograms per cubic meter per year. The world average is 70 micrograms, while the most polluted cities have exceeded the guidelines by an astronomical 15 times, or about 300 micrograms.
The Iranian city of Ahwaz has the highest levels of any of the 1,100 cities worldwide that were studied by the WHO, with about 372 micrograms. Three other Iranian cities were in the bottom 10 in air quality. The other cities with poor air quality can be found in Mongolia, India, Pakistan, and Botswana. (A complete list can be found here.)
"Solutions to outdoor air pollution problems in a city will differ depending on the relative contribution of pollution sources, its stage of development, as well as its local geography," said Dr. Carlos Dora, WHO Coordinator for Interventions for Health Environments in the Department of Public Health and Environment. "The most powerful way that the information from the WHO database can be used is for a city to monitor its own trends in air pollution over time, so as to identify, improve and scale-up effective interventions."
This interactive map is one of those tools to show which countries need to do more to clean up their cities. Every city is different, but solutions like tailpipe emissions and cleaning up emissions from power plants is a start. Renewable energy would, of course, make a huge impact on emissions from dirty coal plants. While the U.S. still relies on coal and cars, regulations on air quality means they are below the WHO's recommended air quality guidelines.
Taking any step to lower air pollution in our cities has a direct correlation with a lower global death rate. If the world average dropped from 70 micrograms to the recommended average, 20 micrograms, the mortality rate would decline by 15 percent. A huge win for global health.